https://peertube.magdowski.de/videos/watch/5d49eb2a-4f49-4114-a875-9c4be3c4a9b9 In this live-streamed exercise in the "Electromagnetic Compatibility" module, we are discussing the solution of task 14 of our exericse booklet on field impedance. At a distance of 1m in front of the screen surface of a monitor, an electric field strength with a level of L_E = 83 dB(µV/m) at 22.5 kHz (horizontal scan rate of a cathode-ray tube display) has been measured. How large is the magnetic field strength if the source is assumed to be a) an electric interference source or b) a magnetic interference source? Exercise booklet: print version: https://cloud.ovgu.de/s/PTfXwD74kwbYaYM smartphone version: https://cloud.ovgu.de/s/KKoQeBJdimFzwWg Lecture slides: https://cloud.ovgu.de/s/rmDBzgykbsEdkeS Notes: https://cloud.ovgu.de/s/3pmRfPM4QotKRod GNU Octave commands: clear all clc L_E=83 f=22.5e3 E=10^(L_E/20)1e-6 E1e3 c=3e8 lambda=c/f lambda/1e3 r_0=lambda/2/pi eta_0=377 r=1 eta_electric=eta_0r_0/r eta_electric/1e3 H_electric=E/eta_electric H_electric1e9 eta_magnetic=eta_0r/r_0 H_magnetic=E/eta_magnetic L_H_electric=20log10(H_electric/1e-6) L_H_magnetic=20log10(H_magnetic/1e-6) L_eta_electric=20log10(eta_electric/1) L_eta_magnetic=20*log10(eta_magnetic/1) L_E-L_eta_electric L_E-L_eta_magnetic Chapter marks: 00:00 Welcome and explanation of the task 02:29 Conversion of the level into a field strength 07:49 Field impedance 16:23 Calculation in GNU Octave 26:34 Practical aspects 29:17 Calculation with levels in dB 44:30 Discussion of the dB calculation Fri, 19 Jun 2026 10:08:03 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://peertube.magdowski.de https://peertube.magdowski.de/lazy-static/avatars/df74db12-5ddc-45c0-afab-4cdf2486a5a1.jpg https://peertube.magdowski.de/videos/watch/5d49eb2a-4f49-4114-a875-9c4be3c4a9b9 All rights reserved, unless otherwise specified in the terms specified at https://peertube.magdowski.de/about and potential licenses granted by each content's rightholder.